(mbswidth): Add a flags argument.

(mbsnwidth): New function.

diff --git a/lib/mbswidth.c b/lib/mbswidth.c
index 09777c5b5ee3e1fb34b521c60e7b3d2ced34c4a3..d187bc06858564b921f11f6fa7fa407ace68d825 100644 (file)
--- a/lib/mbswidth.c
+++ b/lib/mbswidth.c
@@ -69,7 +69,6 @@ int wcwidth ();
 /* wcwidth doesn't exist, so assume all printable characters have
    width 1.  */
 #  define wcwidth(wc) ((wc) == 0 ? 0 : iswprint (wc) ? 1 : -1)
-# else
 # endif
 #endif
 
@@ -85,15 +84,27 @@ int wcwidth ();
 #undef ISPRINT
 #define ISPRINT(c) (ISASCII (c) && isprint (c))
 
+#include "mbswidth.h"
+
 /* Returns the number of columns needed to represent the multibyte
    character string pointed to by STRING.  If a non-printable character
-   occurs, -1 is returned.
-   This is the multibyte analogon of the wcswidth function.  */
+   occurs, -1 is returned, unless MBSW_ACCEPT_UNPRINTABLE is specified.
+   With flags = 0, this is the multibyte analogon of the wcswidth function.  */
 int
-mbswidth (const char *string)
+mbswidth (const char *string, int flags)
+{
+  return mbsnwidth (string, strlen (string), flags);
+}
+
+/* Returns the number of columns needed to represent the multibyte
+   character string pointed to by STRING of length NBYTES.  If a
+   non-printable character occurs, -1 is returned, unless
+   MBSW_ACCEPT_UNPRINTABLE is specified.  */
+int
+mbsnwidth (const char *string, size_t nbytes, int flags)
 {
   const char *p = string;
-  const char *plimit = p + strlen (p);
+  const char *plimit = p + nbytes;
   int width;
 
   width = 0;
@@ -127,8 +138,6 @@ mbswidth (const char *string)
              p++;
              width++;
              break;
-           case '\0':
-             break;
            default:
              /* If we have a multibyte sequence, scan it up to its end.  */
              {
@@ -137,20 +146,32 @@ mbswidth (const char *string)
                do
                  {
                    wchar_t wc;
-                   size_t bytes = mbrtowc (&wc, p, plimit - p, &mbstate);
+                   size_t bytes;
                    int w;
 
-                   if (bytes == 0)
-                     /* A null wide character was encountered.  */
-                     break;
+                   bytes = mbrtowc (&wc, p, plimit - p, &mbstate);
 
                    if (bytes == (size_t) -1)
                      /* An invalid multibyte sequence was encountered.  */
-                     return -1;
+                     {
+                       if (flags & MBSW_ACCEPT_INVALID)
+                         break;
+                       else
+                         return -1;
+                     }
 
                    if (bytes == (size_t) -2)
                      /* An incomplete multibyte character at the end.  */
-                     return -1;
+                     {
+                       if (flags & MBSW_ACCEPT_INVALID)
+                         break;
+                       else
+                         return -1;
+                     }
+
+                   if (bytes == 0)
+                     /* A null wide character was encountered.  */
+                     bytes = 1;
 
                    w = wcwidth (wc);
                    if (w >= 0)
@@ -158,7 +179,10 @@ mbswidth (const char *string)
                      width += w;
                    else
                      /* An unprintable multibyte character.  */
-                     return -1;
+                     if (flags & MBSW_ACCEPT_UNPRINTABLE)
+                       width += 1;
+                     else
+                       return -1;
 
                    p += bytes;
                  }
@@ -174,10 +198,7 @@ mbswidth (const char *string)
     {
       unsigned char c = (unsigned char) *p++;
 
-      if (c == '\0')
-       break;
-
-      if (ISPRINT (c))
+      if ((flags & MBSW_ACCEPT_UNPRINTABLE) || ISPRINT (c))
        width++;
       else
        return -1;